1) Field of the Invention
The present invention relates to an image forming apparatus such as a copier, printer, facsimile, etc., and more particularly, to an image forming apparatus that includes a photosensitive element bearing a toner image on its outer surface and a transfer member in the form of an endless belt being pressed against by the outer surface of the photosensitive element, and that cleans residual toner that is not transferred to a recording medium and is left over on the transfer member, and collects the residual toner in a waste-toner receptacle.
2) Description of the Related Art
Image forming apparatuses that include an intermediate transfer belt directly presses against by the outer surface of a photosensitive element or a recording-medium conveying belt pressed against by the outer surface of the photosensitive element with a recording medium sandwiched between the recording-medium conveying belt and the photosensitive element, and in which a toner image formed on the outer surface of the photosensitive element is transferred to the recording medium have come to be widely used, and with it there is an increasing call for making such image forming apparatuses compact.
One way of achieving compactness in an image forming apparatus that includes an intermediate transfer belt and a recording-medium conveying belt is by using the space available on the undersurface of the intermediate transfer belt or the recording-medium conveying belt that comprise a transfer member in the form of an endless belt. For instance, in the image forming apparatuses disclosed in Japanese Patent Laid-Open Publication No. 2002-62776 and Japanese Patent Laid-Open Publication No. 2002-296922, a waste toner receptacle that cleans and recovers the residual toner left over after the toner image is transferred to the recording medium, is located in the space on the undersurface of the transfer member in the form of an endless belt.
In the invention disclosed in Japanese Patent Laid-Open Publication No. 2002-62776, the waste toner receptacle (waste toner recycling receptacle) detachably set in the image bearing unit, and the entire image bearing unit together with the waste toner receptacle is detachable from the main unit. However, it is not possible to only remove the image bearing body from the main unit without the waste toner receptacle. This feature is disadvantageous since every time the image bearing unit has to be removed for either replacement or overhauling, the waste toner receptacle also comes out with it, leading to a possibility of spillage of the toner inside the image forming apparatus.
Further, in the invention disclosed in Japanese Patent Laid-Open Publication No. 2002-62776, two separate waste toner receptacles are provided for collecting the waste toner recovered by cleaning the image bearing unit and the waste toner recovered by cleaning the photosensitive element.
In the invention disclosed in Japanese Patent Laid-Open Publication No. 2002-296922, even though it is possible to replace the intermediate transfer belt with the waste toner receptacle still mounted in the image forming apparatus, replacing or servicing the intermediate transfer belt takes effort since it involves removing the intermediate transfer from the rollers that support it.